Sheet-metal thumb-nut.



H. F. LARAVA.

.SHEET METAL THUMB NUT.

APPLIOATION FILED 11:11.17, 1912,

Patented Nov. 19, 1912.

M'nesse' normar.

cheaply,

HENRY F. LARAVA, F WORCESTE, MASSACHUSETTS. ASSIGNOB TO lQ'U'Ill'slG'AIDIDDNID PRESSED STEEL AND TOOL COMPANY, 0F

Specication of Lettersilatent.

WoncEsTEn, nnssacnusnrrrs, A Fran. SHEET-METAL Trium-NUT,

Patented Nov. 19, 1912.

Application led February 17, 1912. Serial No. 673,376.

To all whom 'it may concern:

Be it known that I, HENRY F. LAnAvA, a citizen of the United States, residing at Worcester, in the county of Worcester and State of Massachusetts, have invented a new and useful Sheet-Metal Thumb-Nut, of which the following is a s ecification.

The principal objects o this invention are to provide a thumb nut or the like of such a character that it can be made readily and mostly on presses.

Further objects and advantages of the invention will appear hereinafter.

lReference is to be had to the accompanying` drawings, in which,

igure 1 is a, plan of a blank from which the thumb nutns to be made; Fig. 2 is a similar view showing the second step of the method of manufacture; Fig. '3 is a similar view showingthe completed thumb nut in side elevation; Fig. 4 is a central longitudinalsectional view of the same; an end view thereof.

This invention is made with the idea of making a thumb nut such as shown in Figs. 3, 4 and 5 fromV a blank of sheet metal without machining, except to make a screw and Fig. 5 is thread, and without undue waste of material. For this purpose the first step of the method of manufacture consists in the production by ordinary stamping methods lof-a f blank such as shown in Flg. 1 comprising a pair of arms alocated opposite each other andv bowed outwardly so as practically to constitute a portion of a circle, and having on opposite sides apair of flat circular portions or enlargements 6 each provided with a perforation o. These elements as will` be understood are all in a-single plane as they are stamped out of a piece of sheet steel or other metal. The arms integrally connect the two circular enlargements. .The next step is to twist the two circular enlargements through an angle of substantially degrees so tha they' will come into the position b in Fi 2. This produces a slight twist yin the ends of the arms next to the enlargements and brings the two enlargements into line with each other so that when crushed together as indicated in Fig. 3 'by an ordinary stamping process (the third step) the two perforations o will register with each other as will the other parts of the two enlargements. This is shown in Fig. 3. 'This also results in doubling the' arms a over into substantially the form shown in Fig. 3 in which theyv form hollow wings for the thumb nut. In order to complete the thumb nut the perforations o, now in registration, are provided with a continuous screw thread al. It will be seen therefore that the completed article consists of a nut proper formed of two pieces of sheet metal b forced together face to face and having a continuous screw-threaded hole through them and that the wings of the 4nut are formed by the arms a bent, over each other at the ends.

.This provides a light and simple thumb nut. having substantially the shape now well known in this industry and formed of sheet metal, all parts being integrally connected so that the thumb nut is very strong and durable. On account of the method of manufacture also it will be obviousthat the thumb-nuts will come out vsubstantially uniform and admirably adapted to serve the ypurposes for which they are intended.

l Although I have illustrated and described a preferred embodiment of the invention and a preferred series of steps by which the method is carried out, I am aware that many modifications can be made in both without departing from the scope of the inventionasv expressed in the claims. Therefore I do not wish' to be limited to all the details herein shown and described, or to the precise order of steps indicated, but

What I do claim is 1. As an article of manufacture, a thumb nut having a nut proper consisting of two pieces of sheet metal lying face to face and having opposite arms integral with both pieces.

2. As an article of manufacture, .a thumb nut comprising a nut proper conslstmg of two pieces of perforated sheet metal lying my hand, in the presence of two hscribing 1 face to face, the perforations regsterlng an having a continuous screw thread2 and provided with a pair of opposite wmgs, each 5 consisting of an arm integral with both pieces of sheet metal and bent into a loop.

. In'testimony whereof I have hereunto set wltnesses. v

HENRY F. LARAVA,

Witnesses:

EDWARD D. R. MORRELM dWILLIAM A. DEAN. 

